The present application is related to and claims priority from Japanese Patent Application No. 00-240359, filed Aug. 3, 2000.
The present invention relates to an information recording medium and recorder/reproducer equipment using such medium.
As optical disks for music use, music CDs (Compact Discs) are available that are made by using an optical disk with a diameter of 12 cm (or 8 cm).
These optical disks are available with three types: replay only type (read only memory (ROM): additional recording is impossible), write-once read-many type (additional recording is possible only once), and rewritable type (erasure and recording are possible repeatedly).
Music CDs are primarily the replay only type and data is recorded thereon in order of lead-in area, program area, and lead-out area. Music is stored into a program area in units of pieces of music (area into which one piece of music is to be recorded is called a track) and a plurality of pieces of music (a plurality of tracks) is recorded in a program area. In the lead-in area, TOC (Table of Contents) is recorded to manage the plurality of pieces of music (the start addresses of the pieces of music in the program area are registered therein). By reading the TOC, an optional piece of music can be reproduced from among the pieces of music recorded in the program area.
A multisession recording method is applied to write-once read-many CDs for handling data files to compensate for an intrinsic drawback of these CDs that additional recording is possible just only once. Many kinds of CD-R (Compact Disc-Recordable) drives that support this multisession recording method have been released and put on the market.
On a CD on which data has been recorded by the multisession recording method, a plurality of sessions exist, each of which comprising a lead-in area, a program area, and a lead-out area arranged in this order. In the lead-in area of each session, the start address of the next session""s program area is recorded and algorithm is designed such that the sessions are accessed sequentially, thereby reaching the last session.
Write-once read-only CDs to handle data files have a directory for managing files in every session and files existing in other sessions can be managed under this directory.
However, write-once read-only CDs for music use do not have the directory for managing files and it has been impossible to use them satisfactorily with multisession. Specifically, after music information is recorded onto these CDs, once the sessions of CD have been finalized and closed, additional recording is impossible in spite of free area existing.
In the foregoing prior art, multisession recording is satisfactorily effective for write-once read-only CDs (CDs-R for data use) for handling data files. For these CDs, a directory for managing files exists in every section and files existing in other sessions can be managed under this directory.
On the other hand, multisession recording is not effective for write-once read-only CDs for music use, because these CDs do not have the directory for managing files. Thus, it has been impossible that music information in other sessions be managed and reproduced from a session.
An object of the present invention is to provide a CD for music use that can be used so as to take full advantage of multisession recording and a recorder and/or a reproducer using such CD.
The present invention allows music information to be recorded in multisession format onto an information recording medium. In a music CD onto which music data has been recorded in multisession format according to the present invention, in TOC (Table of Contents) in the lead-in area of one of the multiple sessions of the CD, information for managing pieces of music (tracks) in other sessions is also to be registered.
When data is recorded in multisession format onto an information recording medium, information for managing tracks that are being recorded in a session is registered into TOC (Table of Contents) of the session, and at the same time, information for managing some tracks recorded in other sessions is also optionally selected and registered into the TOC.
A recorder according to the present invention can record music data in multisession format onto an information recording medium as described above.
Then, when information is reproduced from the information recording medium onto which data has been recorded in multisession format according to the invention, sorting is carried out, based on the information for managing tracks from the TOC of the session from which information is to be reproduced and reproduction is carried out, based on the result of the sorting.
When information is reproduced from the information recording medium onto which data has been recorded in multisession format according to the invention, track numbers beginning with 1 (new track numbers to be assigned are to be called logical track numbers, which also applies to the remaining part of the specification) are assigned to the tracks managed in the TOC of the session from which information is to be reproduced, based on the information for managing the tracks from the TOC. After sequence in which the tracks are replayed is determined and reproducing process is carried out, when the logical track numbers of the tracks to be replayed may be displayed on the display section or output to an external display device. Furthermore, based on the set logical track numbers, user setting of programming and replay and reproducing process according the programming and replay can also be performed.
A reproducer according to the present invention is to be able to carry out the above sorting and logical number assignment, based on the information for managing tracks from the TOC of an arbitrary session of the information recording medium onto which music data has been recorded in multisession format as described above, and execute reproducing process by using the logical numbers of the tracks.